Pubs-injection vai



vwemtoz B. C. SMITH FUELINJECTION VALVE Filed May 14,

Aug. 25, 19-25.

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Patented Aug.. 25, 1925.

UNlTEDjsTATEs PATENT oFFlcE-.-

BENJAMIN C. SMITH, OF BAYONNE, NEW JERSEY, ASSIGNOR 4TO STANDARD MOTOR CONSTRUCTION COMPANY, O'F JERSEY CITY, NEW JERSEY, A CORPORATIONOF NEW JERSEY.

FUEL-INJECTION' VALVE.

Application med my 14, 1925. serial No. 30,202.

residing at Bayonne, New Jersey, have in vented a new and useful Fuel-Injection Valve, of which the following is a specifical tion.

f before the valve may be opened.

My invention relates to a valve and particularly to a high pressure fuel injection valve f for an oil engine.

The introduction of fuel into the cylinder of an o-il burning engine is usually at a very high pressure. In the valves with which I am familiar, the static pressure of the high pressure fuel acting -below the valve when the valve is off its seat'has required exceedingly heavy springs for urgin the valve onto its seat and the mechanism or raising the same must act against and overcome the pressure of the exceedingly stift' and heavy springs These heavy springs sometimes cause the valve stem to buckle and there are other disadvantages attendant upon the use of such.

very heavy springs. l l

, It is the general object of my invention, therefore, to overcome in alarge measure,

' the dilliculties above'pointed out.

. spring may be employed for'urging the It is a more specificob'ect to provide a valve which will be partly alanced so far as fluid pressure is concerned when the valve is olf its seat.

It is a` further bject to provide a valve.

for high pressure fluids whereina relatively light spring will suice to force the valve onto its seat.

It is a still more specific object to providea valve with a tension member, for actuating the same, formed of'piano wire-or the like. Other objectsf'will appear as thespeci-v fication proceeds.

Briefly stated, in the preferred' form of `the invention I employ a valvesubstanv tially all of which issubjected to the fluid pressure when the valve is oli' itsv seat. A

valve onto its seat.A kA tension member of comparatlvel small cross-section, preferablyl in tle crm of a high tensile strength material such as piano wire, is attached to `the valve and passes .through a stufng box, on theoutside ofv which 1t is attached to mechanism for raising the' valve at the proper moment. The tension member being of smaller cross section than the valve per- Ionto vthe lower end thereof. 10 indicates a mits the latter torbe partly balanced so that a relatively lightt spring may-be employed since such spring need be only slightly stronger than isrequired to overcome friction and the unbalanced static pressure acting upon area equivalent to the cross section of the tension member. y

In the drawin s which show, for illustrative purposes on y, a vpreferred form of the lnventlon: i Fig.- 1 is a sectional view through a'valve illustrating features of my invention and employing valve actuating mechanismof conventional type;

Fig. 2 is a relatively enlarged fragment-ary sectional valve.

In said drawings, 1 indicates whatfmay be tei-med a valve casing having .a fluid' inlet port 2 communicating with passages 3,4 and -5, leadin tothe ports 6-6 in the valve seat 7. It wi l be understood that the valve casing up to thef-boss h-aving `the inlet 2, will be passed-'through a suitable bore in the cylinder 'head 'and secured therein.

In theform shown, the lower end of the casing 1 may #be threadeda'to 'receive the coupling 8 securing a valve. seat sleeve 9 valve member which in the form shown is connection 2` the valve casing may-have a 95 bore 12 whichfmay fit the valve memberr 10 quite closely so asto act asf an additional guide. Y f l "f, At the upper` end of the casin 1, there ispreferablyA provided what may e termed y 100 f a spring lhousing-13 closed at the top by'v means of a plug 14 carrying the-packing 15H and the gland-lwhich vlatter is urged onto the ,packing by means of the nut 17 for forming a tight stuilin box forthevalve 105 actuating tension mem er -to be described. At the upper en'd of thevalve member l0-there may be a nut or other abutment 18 preferably rigidly secured thereon-,and

serving .as an abutment for the lower en'd of 1.10

7() view of the lower end of the a relatively long rod formed at the lower lfluid pressure is concerned vexcept for the the spring 19, the otherend of which acts l the valve. It will be obvious that the spring 19 is designed to urge the valve member 10 downwardly onto its seat 7 and the spring should be of such strength as to overcome the unbalanced staticiiuid pressure, the 'friction of the various parts, and to effect the required speed of operation.v Now in order to reduce the unbalanced static pressure of the fluid acting on the valve when it is unseated I prefer to make a. valve raising tension member 2l of a crosssection. relatively smaller than that of the valve member. I have found that a member formed of high tensile strength material, such as piano wire, is admirably suited for raising the valve member and since the spring 19 acts continually, the actuating member 21 will always be under tension and never under compression while the valve member is raised. In the form shown, I attach the lower end of the tension member to a nut 22 which is secured to the abutment 18 and consequently to the valve member 10. The valve actuating tension member passes through the plug and stuffing box heretofore described and the upper end is secured vby suitable means to a lever 23 pivoted to the engine at 24. The cam 25 acting through the bell crank follower 26 serves by means of the connecting link, 27 to oscillate the lever 23 and raise the valve at the proper moment.'

Now it will be obvious that when the valve member 10 is off its'seat the fiuid pressure through the inlet 2 will act above and below theA valve since all parts vare in communication wlth the -fiuid inlet and the parts 6--6 are relatively restricted, and the valve will area of the valve actuating tension member 21- and'since this member is purposely made of smaller cross-section than the valve, the iiuid pressure will be partly balanced and the spring 19 may therefore be relatively light. When the valve is seated, the Huid pressure is, of course, unbalan d and the static pressure urging the valve oward its seat is proportional tothe area of that portion ot' the valve which is seated less the area of the tension member 21. It will thus be .seen that a relatively light spring may be employed with a valve made in accor ance with my invent-ion and, therefore the valve raising member 21may be of relatlvely small crosssection, particularly. since it is never under compression but is always under tension when actlve.

While the invention has been described in some detail and for a speciiic use, I do not wish to be confined to the specific. form shown nor to the specific use since changes may be made within the scope of the invention as defined in the appended claims.

I claim: `1. In a valve, a valve casing having a valve seat therein, a valve member to cooperate with said seat, a piano wire of relatively small cross-section attached to said valve member for raising the latter from the seat, said piano Wire extending through a stuiing box in the valve casing,` a spring in the valve casing for urging said valve member onto the seat, said valve member and spring being in communication With the Huid in said valve easing whereby when the valve member is in open position theluid lpressure tending to force said valve member away from the seat will be the fluid pressure acting upon the area ofthe piano wire, and when the valve is seated the fluid pressure tending to force' the valve onto the seat will be the pressure acting upon the area of that portion of the valve on the seat less the area of the piano wire.

2. In a valve a valve casing having a valve seat, a valve member to cooperate with said seat, a spring for urging said valve member onto the seat, a tension memberoic relatively small cross-'section attached to said valve member -and extending to the outside oi said valve casing, said valve member and 'i part of said tension member being in communication with the fluid in t-he valve casing whereby when the valve member is ofi'- its seatthe Huid pressure acting thereon will be substantially balanced except for the area of the tension member.

3. In a valve, a valve casing having Va valve seat therein, a valve member to cooperate with said seat, and a piano wire tension member for raising said valve member from the seat. f' y 4. In a valve,a,v valve casing having a valve seat therein, a relatively long valve member guided in said casing, said casing having a fluidl inlet therein and a passage along the valve member, a spring housing on said casing and having a passage opening communication between the valve casing and housing, a spring in said housing for urging said valve member onto the. seat,

a tension member of relatively small crosssection extending into said spring housing and attached to said valve member for rais- A ing the latter from the seat, whereby when the valve member is off its seat the Huid pressure acting on the lvalve member will be substantially balanced except for the area of the tension' member.

BENJAMIN c. SMITH. 

